A228761 Primes of the concatenated form 149x149 for some number x.

1496149, 1497149, 1499149, 14915149, 14924149, 14925149, 14928149, 14931149, 14942149, 14945149, 14951149, 14976149, 14985149, 14991149, 149124149, 149127149, 149132149, 149135149, 149150149, 149153149, 149159149, 149162149, 149171149, 149175149, 149187149, 149192149

Offset

1,1

Comments

Sequence is infinite. - Charles R Greathouse IV, Sep 03 2013

Links

K. D. Bajpai, Table of n, a(n) for n = 1..2000

Formula

Primes of the form parse(cat(149,x,149)).

Example

a(1)= 1496149 is a term in the sequence as it is a prime of the form abcxabc:  abc are square digits 1,4 and 9 in order.

Maple

with(StringTools): KD:= proc() local a, b;  a:= 149; b:=parse(cat(a, x, a)); if isprime(b) then RETURN(b):  fi; end: seq(KD(), x=1..1000);

Mathematica

With[{c={1, 4, 9}}, Select[Table[FromDigits[Join[c, IntegerDigits[n], c]], {n, 200}], PrimeQ]](* Harvey P. Dale, Jan 14 2015 *)

Prog

(PARI) for(x=1, 1e3, if(ispseudoprime(t=eval(Str(149, x, 149))), print1(t", "))) \\ Charles R Greathouse IV, Sep 03 2013

Crossrefs

Sequence in context: A128837 A297881 A335289 * A206060 A251973 A236499

Adjacent sequences: A228758 A228759 A228760 * A228762 A228763 A228764

Keyword

nonn,base,less

Author

K. D. Bajpai, Sep 03 2013

Status

approved